LONDON: In a first, British researchers have devised a simple blood test that can be used to diagnose whether people have cancer or not.

Early results have shown the new test gives a high degree of accuracy in diagnosing cancer and pre-cancerous conditions from the blood of patients with melanoma, colon cancer and lung cancer.

The test will enable doctors to rule out cancer in patients presenting with certain symptoms, saving time and preventing costly and unnecessary invasive procedures, researchers said.

"We found that people with cancer have DNA which is more easily damaged by ultraviolet light than other people, so the test shows the sensitivity to damage of all the DNA -- the genome -- in a cell," explained professor Diana Anderson from the University of Bradford's School of Life Sciences.

White blood cells are part of the body's natural defence system. They go under stress when they are fighting cancer or other diseases.

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